Pythia

Authors who mention the oracle include Aeschylus, Aristotle, Clement of Alexandria, Diodorus, Diogenes, Euripides, Herodotus, Julian, Justin, Livy, Lucan, Nepos, Ovid, Pausanias, Pindar, Plato, Plutarch, Sophocles, Strabo, Thucydides, and Xenophon.

Nevertheless, details of how the Pythia operated are scarce, missing, or non-existent, as authors from the classical period (6th to 4th centuries BC) treat the process as common knowledge with no need to explain.

[8] One of the main stories claimed that the Pythia delivered oracles in a frenzied state induced by vapours rising from a chasm in the rock, and that she spoke gibberish which priests interpreted as the enigmatic prophecies and turned them into poetic dactylic hexameters preserved in Greek literature.

[9] This idea, however, has been challenged by scholars such as Joseph Fontenrose and Lisa Maurizio, who argue that the ancient sources uniformly represent the Pythia speaking intelligibly, and giving prophecies in her own voice.

[14] Etymologically, the Greeks derived this place name from the verb πύθειν (púthein) 'to rot',[15] which refers to the sickly sweet smell from the decomposing body of the monstrous Python after it was slain by Apollo.

[20] It describes in detail how Apollo chose his first priests, whom he selected in their "swift ship"; they were "Cretans from Minos' city of Knossos" who were voyaging to sandy Pylos.

During the Greek Dark Age, from the 11th to the 9th century BC,[27] a new god of prophecy, Apollo, was said to have seized the temple and expelled the twin guardian serpents of Gaia, whose bodies he wrapped around the caduceus.

Later myths stated that Phoebe or Themis had "given" the site to Apollo, rendering its seizure by priests of the new god justified, but presumably having to retain the priestesses of the original oracle because of the long tradition.

[citation needed] Diodorus explained how, initially, the Pythia was an appropriately clad young virgin, for great emphasis was placed on the Oracle's chastity and purity to be reserved for union with the god Apollo.

Three oracles had successively operated in Delphi – the chthonion using egkoimisi (a procedure that involved sleeping in the holy place, so as to experience a revealing dream), the Kliromanteion and finally the Apollonian, with the laurel.

[36] The archaeologist John Hale reports that: the Pythia was (on occasion) a noble of aristocratic family, sometimes a peasant, sometimes rich, sometimes poor, sometimes old, sometimes young, sometimes a very lettered and educated woman to whom somebody like the high priest and the philosopher Plutarch would dedicate essays, other times who could not write her own name.

Priestesses enjoyed many liberties and rewards for their social position, such as freedom from taxation, the right to own property and attend public events, a salary and housing provided by the state, a wide range of duties depending on their affiliation, and often gold crowns.

[38] During the main period of the oracle's popularity, as many as three women served as Pythia, another vestige of the triad, with two taking turns in giving prophecy and another kept in reserve.

The Pythia would then bathe naked in the Castalian Spring, then drink the holier waters of the Cassotis, which flowed closer to the temple, where a naiad possessing magical powers was said to live.

The Oracle then descended into the adyton (Greek for 'inaccessible') and mounted her tripod seat, holding laurel leaves and a dish of Kassotis spring water into which she gazed.

Nearby was the omphalos (Greek for 'navel'), which was flanked by two solid gold eagles representing the authority of Zeus, and the cleft from which emerged the sacred pneuma.

Petitioners drew lots to determine the order of admission, but representatives of a city-state or those who brought larger donations to Apollo were secured a higher place in line.

Most commonly,[59] these refer to an observation made by Plutarch, who presided as high priest at Delphi for several years, who stated that her oracular powers appeared to be associated with vapors from the Kerna spring waters that flowed under the temple.

The oleander fumes (the "spirit of Apollo") could have originated in a brazier located in an underground chamber (the antron) and have escaped through an opening (the "chasm") in the temple's floor.

This explanation sheds light on the alleged spirit and chasm of Delphi, that have been the subject of intense debate and interdisciplinary research for the last hundred years.

Adolphe Paul Oppé published an influential article[65] in 1904, which made three crucial claims: No chasm or vapor ever existed; no natural gas could create prophetic visions; and the recorded incidents of a priestess undergoing violent and often deadly reactions was inconsistent with the more customary reports.

[66] In accordance with this definitive statement, such scholars as Frederick Poulson, E. R. Dodds, Joseph Fontenrose, and Saul Levin all stated that there were no vapors and no chasm.

[67] During the 1980s, the interdisciplinary team of geologist Jelle Zeilinga de Boer,[68] archaeologist John R. Hale,[69] forensic chemist Jeffrey P. Chanton,[70] and toxicologist Henry R. Spiller[71] investigated the site at Delphi using this photograph and other sources as evidence, as part of a United Nations survey of all active faults in Greece.

The rift of the Gulf of Corinth is one of the most geologically active sites on Earth; shifts there impose immense strains on nearby fault lines, such as those below Delphi.

Additionally, they discovered at the site formations of travertine, a form of calcite created when water flows through limestone and dissolves calcium carbonate, which is later redeposited.

Further investigation revealed that deep beneath the Delphi region lies a bituminous deposit, rich in hydrocarbons and full of pitch, that has a petrochemical content as high as 20%.

Friction created by earthquakes heat the bituminous layers resulting in vaporization of the hydrocarbons which rise to the surface through small fissures in the rock.

[75] Anesthesiologist Isabella Coler Herb found that a dose of ethylene gas up to 20% induced a trance in which subjects could sit up, hear questions and answer them logically, though with altered speech patterns, and they might lose some awareness and sensitivity in their hands and feet.

[76] During 2001, water samples from the Kerna spring, uphill from the temple and now diverted to the nearby town of Delphi, yielded evidence of 0.3 parts per million of ethylene.

[80] Frequent earthquakes produced by Greece's location at the clashing intersection of three tectonic plates could have caused the observed cracking of the limestone, and the opening of new channels for hydrocarbons entering the flowing waters of the Kassotis.

The omphalos in the museum of Delphi
The Oracle of Delphi Entranced by Heinrich Leutemann
View of Delphi with Sacrificial Procession by Claude Lorrain
Modern photograph of the ruins of the Temple of Apollo at Delphi
Priestess of Delphi (1891) by John Collier , showing the Pythia sitting on a tripod with vapor rising from a crack in the earth beneath her